2 answers

You can use LASF.lsp from my website. That isolates layers by setting current to the first object picked and all other objects layers selected will also not be frozen, but all objects layers not selected will be frozen. LASF = LAYER SET - FREEZE THE REST. It also has an UNLASF function to return the layer settings to their previous setting. That, however, does not work for XREF layers.
http://my.sterling.net/~bdeshawnLook for Free AutoLISP/Visual Lisp routines.

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